Bale openers are used to roughly detach fibers of natural or synthetic origin from fiber bales. There are different types of bale openers, including, among others, those for which the bales are placed close to each other and one arm of the machine slowly travels over, while it detaches and sucks away individual fiber lumps. Since multiple bales are placed side by side, a mixture of the fiber lumps of various bales already takes place here. This improves the mixture. With other known bale openers, each bale opener weighs its fiber material and delivers it to the associated conveying device. Such bale openers are designed, for example, as weighing tray feeders, with which only a specific predetermined quantity of fibers is delivered. Processed materials are, for example, chemical fibers made of PP (polypropylene), PA (polyamide), PES (polyester), etc.
The removal of the opened and weighed fiber material takes place either by means of a conveyor belt, onto which the fiber material plucked off from the bale row falls or is deposited. Alternatively, the detached fiber material is transported away by means of a suction conveyor. The opened and possibly mixed fiber material is generally collected or fed to a subsequent processing machine, such as a carding engine, a carding machine or the like, which is equipped with a tray feeder or a filling shaft as a feeding device.
Frequently, multiple bale openers are placed next to each other, in order to increase the throughput and to make the mixture more effective by means of joint conveyance on the conveyor belt. However, the total number of bale openers is given an upper limit of, as a rule, up to six machines, since—without retrofittings of the participating devices—the fiber volume from the available conveying devices (that is, the conveyor belt(s)) can no longer be handled. Also, the scales placed on the transport path are not capable of weighing very large quantities of fiber.